1. Field of the Invention
The present invention relates to a scanning endoscope system, and in particular to a scanning endoscope system that acquires an image by scanning an object.
2. Description of the Related Art
In respect to an endoscope in a medical field, there have been proposed various techniques for decreasing a diameter of an insertion portion to be inserted into a body cavity of a subject to be examined in order to reduce a burden on the subject. Further, as an example of such techniques, there are known a scanning endoscope that does not include a solid-state image pickup device at a portion corresponding to the above-mentioned insertion portion, and a system that is configured to include the scanning endoscope.
Specifically, the system including the scanning endoscope is configured such that the object is two-dimensionally scanned in a preset scanning pattern by swinging a distal end portion of an illumination fiber that guides illumination light emitted from a light source section, and return light from the object is received by a receiving fiber arranged around the illumination fiber, and an image of the object is generated based on the return light received by the receiving fiber. Then, there is known a scanning beam system disclosed in U.S. Patent Application Publication No. 2008/0218824, for example, which has a configuration similar to the configuration of such a system.
Incidentally, in the conventional scanning endoscope as described above, it is configured that the illumination fiber is swung by applying a voltage to an actuator formed by using a piezoelectric device which is subjected to polarization processing in advance.
Further, in U.S. Patent Application Publication No. 2008/0218824, there is disclosed a configuration in which an optical fiber corresponding to the above-mentioned illumination fiber is swung by applying an AC voltage in accordance with a drive signal having positive and negative amplitudes with “0” as a center.